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P0103

DTC P0103 MAF SENSOR




Component Description
The mass air flow sensor is placed in the stream of intake air. It measures the intake flow rate by measuring a part of the entire intake flow. It consists of a hot film that is supplied with electric current from the ECM. The temperature of the hot film is controlled by the ECM a certain amount. The heat generated by the hot film is reduced as the intake air flows around it. The more air, the greater the heat loss. Therefore, the ECM must supply more electric current to maintain the temperature of the hot film as air flow increases. The ECM detects the air flow by means of this current change.

Consult-II Reference Value In Data Monitor Mode:






On Board Diagnosis Logic:






Fail-Safe Mode:






DTC Confirmation Procedure

NOTE: If "DTC Confirmation Procedure" has been previously conducted, always turn ignition switch "OFF" and wait at least 10 seconds before conducting the next test.

PROCEDURE FOR DTC P0103

With CONSULT-II
1. Turn ignition switch "ON".




2. Select "DATA MONITOR" mode with CONSULT-II.
3. Wait at least 5 seconds.
4. If DTC is detected, go to "Diagnostic Procedure" below. If DTC is not detected, go to next step.
5. Start engine and wait at least 5 seconds.
6. If DTC is detected, go to "Diagnostic Procedure" below.

With GST
Follow the procedure "With CONSULT-II" above.

EC-MAFS-01:







Wiring Diagram

Diagnostic Procedure Step 1 - 3:




Diagnostic Procedure Step 4 - 6:




Diagnostic Procedure Step 7 - 9:




Diagnostic Procedure

Component Inspection

MASS AIR FLOW SENSOR
1. Reconnect harness connectors disconnected.
2. Start engine and warm it up to normal operating temperature.







3. Check voltage between ECM terminal 62 (Mass air flow sensor signal) and ground.
4. If the voltage is out of specification, proceed the following.
- Turn ignition switch "OFF".
- Disconnect mass air flow sensor harness connector and reconnect it again.
- Perform steps 2 and 3 again.

5. If NG, remove mass air flow sensor from air duct. Check hot film for damage or dust.
6. If NG, clean or replace mass air flow sensor.